The first question is how to open a scalar for I/O write?

#!/usr/bin/perl -w
use strict;

my $output;

open (OUT, ">", \$output) or die "can't open scalar for out";

print OUT "this is some line\n";
print OUT "this is another line\n";

print "printing the output variable:\n";
print $output;

__END__
OUTPUT.....
printing the output variable:
this is some line
this is another line
[download]

I think you can also open STDOUT like above. Of course then you have to do something else to test rather just print!

Update:Saw Ikegami's code after I posted. That looks great also. I didn't quite understand the context of why you want to do this?